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This study has multiple issues as did the original study it is accompanying but what got published in Nature Medicine https://www.nature.com/articles/s41591-021
by nojokes 5y ago
This study has multiple issues as did the original study it is accompanying but what got published in Nature Medicine https://www.nature.com/articles/s41591-021-01630-0 https://www.nature.com/articles/s41591-021-01630-0
First the original study did not stratify based on age and sex - a huge failure because potential issue among young men was well known problem.
This preprint tries to fix this but as the original study compared also other cardiac adverse events like pericarditis and cardiac arrhythmias, the preprint does not. It is important because the rate of other complications was not elevated among vaccinated.
This study uses self-controlled case series. This means that they compare against previous incidence rates in the study group (vaccinated, covid-19). This would be possibly more or less fine if they compared two treatments but even then there is big potential for selection bias (the choice of treatment is based on preexisting conditions) but is even higher when you compare treatment and disease - covid-19 is harder for people with comorbidities, when you make a comparison within this group, you can most likely expect higher preexisting prevalence of heart conditions and therefor lower IRR.
This preprint and the orginal paper do not contain any mentioning of unvaccinated. It very likely means that the covid-19 group also contains patients who were vaccinated and had lower rate of AE.
Finally, this study design includes people with previous incidence. Hearth problems are very often recurrent. While it is important to know if vaccination of covid-19 will reintroduce the condition, it is not very interesting for most of the people because incidence rate of these conditions is very low. What is real interest here is how prevalent it is among people who did not have it previously.
Now I am really interested to find out the truth here. This preprint and the orginal study does not help me in this unfortunately.
- nojokes 5y agoI wanted to specify that I find these attempts to but vaccination and covid-19 into perspective very important. This is first study that I know so far has truly attempted to do so. Now in current state they create more confusion and possible harm but they have the data so they should be able to fix these issues.
- jjeaff 5y agohttps://pubmed.ncbi.nlm.nih.gov/34341797/ https://pubmed.ncbi.nlm.nih.gov/34341797/ That study says 6x more likely to get myocarditis from COVID than vaccine. Specifically in young men.
- nojokes 5y agoYes, I know this study. Thanks. I think this is better reference https://www.medrxiv.org/content/10.1101/2021.07.23.21260998v1 https://www.medrxiv.org/content/10.1101/2021.07.23.21260998v... These papers are not directly comparable. Singer et al paper estimates first occurrence of myocarditis without any previous cardiovascular history and without previous vaccination against COVID-19. The OP paper does not have this specification so the results of these papers are not directly comparable. In addition the Singer et al paper includes also pericarditis, myopericarditis (myocarditis and pericarditis occurring together) in addition to myocarditis. Considering that pericarditis is more prevalent in COVID-19 patients and is missing in vaccinated https://www.nature.com/articles/s41591-021-01630-0 https://www.nature.com/articles/s41591-021-01630-0 OP papers clearly is overestimating the difference.
- blindmute 5y agoI completely agree; nothing here is conclusive at all. I just can't stand flippant statements like, "the data is clear," when it isn't, at all. Those kinds of people are directly contributing to the social divide about science.
- nojokes 5y agoI agree.
- jjeaff 5y agoA preprint, but included because it is specifically for young men. 6x more likely to get myocarditis from COVID than vaccine. https://pubmed.ncbi.nlm.nih.gov/34341797/ https://pubmed.ncbi.nlm.nih.gov/34341797/ There are now a multitude of studies indicating the prevelance of myocarditis from COVID 19. Many of which are broken down by age, so you can see how much higher the prevelance is vs vaccine side effects. We have a pretty good idea of how bad the myocarditis issue for COVID is because we had a good long time without a vaccine. There were very large increases in myocarditis in 2020 vs 2019. The real problem is that people like yourself jump to the first contradictory study you can find and tout it as proof or simply muddy the water from what many of the experts are saying. The reality on this particular issue is that quite a bit of research has already been done. A quick search will pull up multiple studies on myocarditis rates with covid, most of which have age breakdowns.
- dannyw 5y agoThat preprint you linked estimates a rate per million of 561 for myocarditis, for young adult males. OP's preprint show a rate per million of 537 for young adult males on their second dose. I would say the research definitely isn't conclusive yet. For young adults, whether the vaccine is safer than getting COVID is an open question, but we do know the absolute risk for both (vaccination or getting COVID) is small.
- nojokes 5y agoThere is one difference: Singer et al paper excludes all patients with previous cardiac incidents.